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1.
Clin Appl Thromb Hemost ; 30: 10760296231223192, 2024.
Article in English | MEDLINE | ID: mdl-38166411

ABSTRACT

To investigate the predictive role of the neutrophil-platelet ratio (NPR) before intravenous thrombolysis (IVT) on hemorrhagic transformation (HT) in patients with acute ischemic stroke (AIS). AIS patients treated with IVT without endovascular therapy between June 2019 and February 2023 were included. Patients were divided into high NPR (>35) and low NPR (≤35) groups according to the optimal threshold NPR value for identifying high-risk patients before IVT. The baseline data and the incidence of HT and symptomatic intracranial hemorrhage (sICH) were compared between the two groups. The predictive role of the NPR and other related factors on HT after IVT was analyzed by multivariate logistic regression. A total of 247 patients were included, with an average age of 67.5 ± 12.4 years. Post-thrombolytic HT was observed in 18.6% of the patients, and post-thrombolytic sICH was observed in 1.2% of the patients. There were 69 patients in the high NPR group and 178 patients in the low NPR group. The incidence of HT in the high NPR group was significantly higher than that in the low NPR group (30.4% vs 16.3%, P < .05). The incidence of sICH was significantly higher in the high NPR group than in the low NPR group (14.5% vs 1.7%, P < .001). Multivariate logistic regression analysis showed that NPR > 35 was positively correlated with HT (odds ratio (OR) = 3.236, 95% confidence interval (CI): 1.481-7.068, P = .003) and sICH (OR = 13.644, 95% CI: 2.392-77.833, P = .003). A high NPR (>35) before IVT may be a predictor of HT in AIS patients. This finding may help clinicians make clinical decisions before IVT in AIS patients.


Subject(s)
Brain Ischemia , Ischemic Stroke , Stroke , Humans , Middle Aged , Aged , Stroke/etiology , Tissue Plasminogen Activator/adverse effects , Ischemic Stroke/drug therapy , Ischemic Stroke/etiology , Neutrophils , Brain Ischemia/etiology , Thrombolytic Therapy/adverse effects , Fibrinolytic Agents/therapeutic use , Intracranial Hemorrhages/chemically induced , Intracranial Hemorrhages/drug therapy , Treatment Outcome
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(3): 608-613, 2023 May.
Article in Chinese | MEDLINE | ID: mdl-37248592

ABSTRACT

Objective: To investigate the status quo of the quality of life of schizophrenia patients in a city in Sichuan Province and to explore, thereof, the urban-rural differences in the factors influencing their quality of life. Methods: A total of 824 schizophrenia patients were selected for the study through multistage stratified cluster random sampling method. All the subjects were selected from a pool of patients covered by the Sichuan Provincial Information System for the Comprehensive Management of Severe Mental Disorders. Questionnaire surveys were conducted with the Schizophrenia Quality of Life Scale (SQLS), the Social Support Rating Scale (SSRS), the general circumstance questionnaire, and the lifestyle questionnaire. In addition, univariate and multiple linear regression models were used to analyze the influencing factors of quality of life among schizophrenia patients living in urban areas and those in rural areas. Results: Rural patients had poorer quality of life than urban patients did in all measurement domains ( P<0.05). Marital status, vocational skills, physical exercise, and social support were influencing factors of the quality of life among urban patients ( P<0.05). Age, marital status, annual household income, vocational skills, participation in community rehabilitation activities, and the time required to walk to the nearest medical institution were influencing factors of the quality of life among rural patients ( P<0.05). Conclusion: Targeted measures for the enhancement of the quality of life of schizophrenia patients should be formulated on the basis of urban and rural characteristics in terms of economic support, vocational skills training, input in mental health services, community rehabilitation services, and social support.


Subject(s)
Quality of Life , Schizophrenia , Humans , Surveys and Questionnaires , Urban Population , Rural Population , China
3.
BMC Oral Health ; 23(1): 82, 2023 02 07.
Article in English | MEDLINE | ID: mdl-36750809

ABSTRACT

BACKGROUND: This study proposed a novel maxillary transverse deficiency diagnostic method and evaluated the skeletal Class I and the mild skeletal Class III groups. METHODS: Pre-treatment data from 30 mild skeletal Class III and 30 skeletal Class I patients were collected and uploaded to the Emeiqi Case Management System to design the ideal teeth positions. On these positions, the first bi-molars width was measured at the central fossa and center resistance, the maxillary first bi-premolars width was measured at the central fossa, and the mandibular first bi-premolars width was measured at the distal contact point by Mimics, then width differences of two groups were calculated respectively. RESULTS: At ideal teeth positions, there was no statistically significant difference in the maxillomandibular width in the premolar area between the two groups, but there was in the molar area, and this difference was caused by the difference in mandible width between the two groups. CONCLUSIONS: We proposed a new transverse diagnostic method and found that even the Class I group was not quite up to standard in the molar area on ideal teeth positions, and the Class III group had more severe maxillary transverse deficiency than the Class I group. Meanwhile, the maxillary transverse deficiency in the Class III group was mainly caused by the larger width of the mandible.


Subject(s)
Malocclusion, Angle Class III , Maxilla , Humans , Mandible , Molar , Bicuspid , Cephalometry
5.
Am J Obstet Gynecol ; 227(3): 479.e1-479.e23, 2022 09.
Article in English | MEDLINE | ID: mdl-35568190

ABSTRACT

BACKGROUND: Embryos with higher morphologic quality grading may have a greater potential to achieve clinical pregnancy that leads to a live birth regardless of the type of cleavage-stage embryos or blastocysts. Few studies have investigated the impacts of embryo grading on the long-term health of the offspring. OBJECTIVE: This pilot study aimed to examine the associations between embryo morphologic quality and the physical, metabolic, and cognitive development of singletons conceived by in vitro fertilization and intracytoplasmic sperm injection at preschool age. STUDY DESIGN: This matched cohort study included singletons born to infertile couples who underwent fresh cleavage-stage embryo transfer cycles with good- or poor-quality embryos from 2014 to 2016 at the reproductive center of the Women's Hospital, School of Medicine, Zhejiang University. A total of 144 children, aged 4 to 6 years, participated in the follow-up assessment from 2020 to 2021, and the response rate of poor-quality embryo offspring was 39%. Singletons in the good-quality embryo group were matched with singletons in the poor-quality embryo group at a 2:1 ratio according to the fertilization method and the children's age (±1 year). We measured the offspring's height, weight, body mass index, blood pressure, thyroid hormone levels, and metabolic indicators. Neurodevelopmental assessments were performed using the Chinese version of the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition, and the Adaptive Behavior Assessment System, Second Edition. We also collected data from the medical records. A linear regression model was used to analyze the association between embryo morphologic quality and offspring health outcomes. RESULTS: A total of 48 singletons conceived with poor-quality embryo transfer and 96 matched singletons conceived with good-quality embryo transfer were included in the final analysis. Age, sex, height, weight, body mass index, blood pressure, thyroid function, and metabolic indicators were comparable between the 2 groups. After adjustment for potential risk factors by linear regression model 1 and model 2, poor-quality embryo offspring exhibited a tendency toward higher free thyroxine levels than offspring of good-quality embryo transfers (beta, 0.22; 95% confidence interval, 0.09-0.90; beta, 0.22; 95% confidence interval, 0.09-0.91, respectively), but this difference was not clinically significant. Regarding neurodevelopmental assessments, there was no difference in the full-scale intelligence quotient based on the Wechsler Preschool and Primary Scale of Intelligence (109.96±12.42 vs 109.60±14.46; P=.88) or the general adaptive index based on the Adaptive Behavior Assessment System (108.26±11.70 vs 108.08±13.44; P=.94) between the 2 groups. The subindices of the 2 tests were also comparable. These findings remained after linear regression analysis. CONCLUSION: At 4 to 6 years of age, singletons born from poor-quality embryo transfers have comparable metabolic and cognitive development as those born from good-quality embryo transfers using fresh cleavage-stage embryos. The results of this pilot study indicate that poor-quality embryos that can survive implantation and end in live birth are likely to have a developmental potential comparable to that of good-quality embryos.


Subject(s)
Semen , Sperm Injections, Intracytoplasmic , Child , Child, Preschool , Cognition , Cohort Studies , Female , Fertilization , Fertilization in Vitro/adverse effects , Humans , Male , Pilot Projects , Pregnancy , Sperm Injections, Intracytoplasmic/adverse effects
6.
Nutrients ; 14(5)2022 Feb 27.
Article in English | MEDLINE | ID: mdl-35267975

ABSTRACT

Vitamin D (VitD) shows a beneficial role in placentation, the immune system, and angiogenesis, and thus, VitD status may link to the risk of preeclampsia. A meta-analysis was conducted to investigate the association between VitD status in early and middle pregnancy and the risk of preeclampsia. A total of 22 studies with 25,530 participants were included for analysis. Women with VitD insufficiency or deficiency had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.58, 95% CI 1.39-1.79). Women with VitD deficiency had a higher preeclampsia rate compared to women with replete or insufficient VitD levels (OR 1.35, 95% CI 1.10-1.66). Women with insufficient VitD levels had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.44, 95% CI 1.24-1.66). Women with deficient VitD levels had a higher preeclampsia rate compared to women with replete VitD levels (OR 1.50, 95% CI 1.05-2.14). Sensitivity analysis showed the results were stable after excluding any one of the included studies. In conclusion, our systematic review suggested that VitD insufficiency or deficiency was associated with an increased risk of preeclampsia.


Subject(s)
Pre-Eclampsia , Vitamin D Deficiency , Female , Humans , Placentation , Pre-Eclampsia/epidemiology , Pregnancy , Vitamin D , Vitamin D Deficiency/complications , Vitamin D Deficiency/epidemiology , Vitamins
7.
Am J Orthod Dentofacial Orthop ; 159(6): 758-765, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33722409

ABSTRACT

INTRODUCTION: The objective of this research was to evaluate the reliability of 2 methods (Andrews' Element III analysis and Yonsei transverse analysis) in maxillary transverse deficiency diagnosis. METHODS: Plaster casts and cone-beam computed tomography images of 80 outpatients with skeletal Class I malocclusion (29 males and 51 females, mean age, 20.16 ± 8.22 years) were selected. Maxillary and mandibular width were measured, respectively, and independently by 2 examiners at an interval of 2 weeks, using Andrews' Element III analysis and Yonsei transverse analysis. Intraclass correlation coefficients and Bland-Altman plots of intraexaminer and interexaminer reliability were evaluated. After diagnosis, Cohen's kappa statistics were calculated to evaluate the diagnostic agreement. RESULTS: The intraclass correlation coefficients were all above 0.85, indicating good to excellent reliability. Compared with Andrews' Element III analysis, Yonsei transverse analysis had higher intraexaminer and interexaminer reliability in both maxillary and mandibular width measurements. Thirty-one to 42 of the patients were diagnosed with maxillary transverse deficiency by 2 examiners using 2 methods. The intraexaminer and interexaminer Cohen's kappa values of Yonsei transverse analysis were all higher than those of Andrews' Element III analysis. CONCLUSIONS: Both Andrews' Element III analysis and Yonsei transverse analysis had good to excellent reliability and substantial diagnostic agreement. Yonsei transverse analysis had higher reliability in maxillary and mandibular width measurements and higher diagnostic agreement, compared with Andrews' Element III analysis.


Subject(s)
Mandible , Tooth , Adolescent , Adult , Child , Cone-Beam Computed Tomography , Female , Humans , Male , Maxilla/diagnostic imaging , Reproducibility of Results , Young Adult
8.
Chin Med J (Engl) ; 134(6): 716-724, 2021 01 05.
Article in English | MEDLINE | ID: mdl-33410621

ABSTRACT

BACKGROUND: Obesity is a fundamental factor in metabolic disorders such as hyperlipidemia, insulin resistance, fatty liver, and atherosclerosis. However, effective preventive measures are still lacking. This study aimed to investigate different surgical protocols for removing partial adipose tissue before the onset of obesity and determine whether, and by which protocol, preliminary adipose removal could exert potent preventive effects against diet-induced metabolic disorders. METHODS: Male low-density lipoprotein receptor (LDL-R) knockout (KO) mice were randomly divided into four groups and subjected to epididymal fat removal (Epi-FR) surgery, subcutaneous fat removal (suQ-FR) surgery, both subcutaneous and epididymal fat removal (Epi + suQ-FR) surgery, or sham-operation. After 1 week of recovery, all mice were given a high-fat diet (HFD) for 10 weeks to induce metabolic disorders. RESULTS: In the Epi-FR group and the sham-operated group, the mean numbers of the residual subcutaneous fat were 28.59 mg/g and 18.56 mg/g, respectively. The expression of relative genes such as Pparg, Cebpa, Dgat2, Fabp4 and Cd36 in the residual subcutaneous fat increased 2.62, 3.90, 3.11, 2.06, 1.78 times in the Epi-FR group compared with that in the sham-operated group. Whereas in the other fat-removal groups, the residual fat depots had no significant change in either size or gene expression, as compared with those of the sham-operated group. Plasma lipid and glucose levels and insulin sensitivity, as detected by the glucose tolerance test, were not significantly alleviated in the three fat removal groups. Liver mass or lipid content was not attenuated in any of the three fat removal groups. The atherosclerosis burdens in the entire inner aorta and aortic root did not decrease in any of the three fat removal groups. CONCLUSIONS: Our data suggest that removal of epididymal adipose or subcutaneous adipose alone or in combination before the onset of obesity did not protect against hyperlipidemia, insulin resistance, fatty liver, or atherosclerosis in LDL-R KO mice fed with a HFD. Hence, adipose removal possibly does not represent a potential approach in preventing obesity-related metabolic disorders in the obesity-susceptible population.


Subject(s)
Adipose Tissue , Insulin Resistance , Animals , Diet, High-Fat/adverse effects , Liver , Male , Mice , Mice, Inbred C57BL , Obesity , Subcutaneous Fat
9.
Am J Orthod Dentofacial Orthop ; 157(3): 329-339, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32115111

ABSTRACT

INTRODUCTION: The purpose of this study was to comparatively evaluate the effects of Twin-block (TB) appliance and sagittal-guidance Twin-block (SGTB) appliance on alveolar bone around mandibular incisors in growing patients with Class II Division 1 malocclusion, using cone-beam computed tomography. METHODS: The sample consisted of 25 growing patients with Class II Division 1 malocclusion (14 boys and 11 girls, mean age 11.92 ± 1.62 years) and was randomly distributed into the TB group (n = 13) and the SGTB group (n = 12). The treatment duration was 11.56 ± 1.73 months. Pretreatment (T1) and posttreatment (T2) cone-beam computed tomography scans were taken in both groups. Height, thickness at apex level, and volume of the alveolar bone around mandibular left central incisors were measured respectively on labial and lingual side, using Mimics software (version 19.0; Materialise, Leuven, Belgium). Based on the stable structures, 3-dimensional (3D) registrations of T1 and T2 models were taken to measure the sagittal displacement of incisors. Intragroup comparisons were evaluated by paired-samples t tests and Wilcoxon tests. Independent-samples t tests and Mann-Whitney U tests were used for intergroup comparisons. RESULTS: In both groups, alveolar bone height and volume on the labial side of the incisors significantly decreased after treatment (P <0.05). Lingual alveolar bone height, lingual and total alveolar bone volume, labial, lingual and total alveolar bone thickness showed no significant difference between T1 and T2 (P >0.05). In both groups the incisors tipped labially and drifted to the labial side. Compared with the TB group, less labial alveolar bone loss, less incisor proclination and crown edge drift were found in the SGTB group (P <0.05). CONCLUSIONS: Labial alveolar bone loss around mandibular incisors was observed after both types of appliances treatment in growing patients with Class II Division 1 malocclusion. Less labial alveolar bone loss, less incisor proclination, and crown edge drift were found in the SGTB group than in the TB group during treatment.


Subject(s)
Alveolar Bone Loss , Malocclusion, Angle Class II , Orthodontic Appliances , Adolescent , Cephalometry , Child , Cone-Beam Computed Tomography , Female , Humans , Incisor , Male , Malocclusion, Angle Class II/diagnostic imaging , Malocclusion, Angle Class II/therapy , Mandible , Tooth Crown
10.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(3): 291-297, 2019 May.
Article in Chinese | MEDLINE | ID: mdl-31631592

ABSTRACT

OBJECTIVE: To explore the biological characteristics of the esterase LipR encoded by Mycobacterium tuberculosis (MTB) Rv3084 and its immunomodulatory function in vivo. METHODS: The LipR gene was amplified from MTB H37Rv strain to construct recombinant expression plasmid. After sequencing, the recombinant plasmid was transformed into E. coli for expression and purification of LipR protein. The expressed protein was confirmed with Western blot assay. The hydrolyzing activity of LipR was detected and the factors affecting LipR enzyme activity were analyzed. Mice were intramuscularly injected with 0.1 mL (containing plasmid DNA 100 µg) recombinant eukaryotic plasmid three times (day 1, 8, and 15); seven days after the last injection, the mice were executed, and the lung and spleen were taken for cytokine detection. RESULTS: The recombinant expression plasmid was successfully constructed and it was found that LipR protein was mainly expressed in the form of inclusion bodies in E. coli with the relative molecular mass of about 33×10 3. LipR was demonstrated as an alkaline eurythermic esterase, due to the preference of hydrolyzing short carbon chain esters with optimal hydrolyzing activity on pNP-acetate (pNPA, C2) and the capability in tolerance of high pH and temperature; in the presence of different detergents or metal ions, the activity of LipR hydrolyzing pNP-butyrate (pNPB, C4) was inhibited to some extent. In the mouse model, it was found that LipR could inhibit the secretion of interferon-γ (IFN- γ) and interleukin-2 (IL-2), but to stimulate the secretion of IL-10. CONCLUSION: The esterase LipR may be one of the esterases help M. tuberculosis withstand harsh environment inside the host in collaboration, and simultaneously act as an immune modulator to inhibit the secretion of pro-inflammatory cytokines and consequently impact the killing effect of host immune system against M. tuberculosis.


Subject(s)
Bacterial Proteins/metabolism , Esterases/metabolism , Interferon-gamma/immunology , Interleukin-10/immunology , Interleukin-2/immunology , Mycobacterium tuberculosis/enzymology , Animals , Mice
11.
Nan Fang Yi Ke Da Xue Xue Bao ; 38(4): 384-389, 2018 Apr 20.
Article in Chinese | MEDLINE | ID: mdl-29735436

ABSTRACT

OBJECTIVE: To observe the protective effects of potassium channel opener nicorandil against cognitive dysfunction in mice with streptozotocin (STZ)-induced diabetes. METHODS: C57BL/6J mouse models of type 1 diabetes mellitus (T1DM) were established by intraperitoneal injection of STZ and received daily treatment with intragastric administration of nicorandil or saline (model group) for 4 consecutive weeks, with normal C57BL/6J mice serving as control. Fasting blood glucose level was recorded every week and Morris water maze was used to evaluate the cognitive behavior of the mice in the 4th week. At the end of the experiment, the mice were sacrificed to observe the ultrastructural changes in the hippocampus and pancreas under transmission electron microscopy; the contents of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) in the hippocampus and SOD activity and MDA level in the brain tissue were determined. RESULTS: Compared with the control group, the model group showed significantly increased fasting blood glucose (P<0.001), significantly prolonged escape latency (P<0.05) and increased swimming distance (P<0.01) with ultrastructural damage of pancreatic ß cells and in the hippocampus; GIP and GLP-1 contents in the hippocampus (P<0.01) and SOD activity in the brain were significantly decreased (P<0.05) and MDA content was significantly increased in the model group (P<0.05). Compared with the model group, nicorandil treatment did not cause significant changes in fasting blood glucose, but significantly reduced the swimming distance (P<0.05); nicorandil did not improve the ultrastructural changes in pancreatic ß cells but obviously improved the ultrastructures of hippocampal neurons and synapses. Nicorandil also significantly increased the contents of GIP and GLP-1 in the hippocampus (P<0.05), enhanced SOD activity (P<0.05) and decreased MDA level (P<0.01) in the brain tissue. CONCLUSION: Nicorandil improves cognitive dysfunction in mice with STZ-induced diabetes by increasing GIP and GLP-1 contents in the hippocampus and promoting antioxidation to relieve hippocampal injury.


Subject(s)
Cognitive Dysfunction/drug therapy , Diabetes Mellitus, Experimental/complications , Nicorandil/pharmacology , Animals , Blood Glucose , Diabetes Mellitus, Experimental/chemically induced , Gastric Inhibitory Polypeptide/metabolism , Glucagon-Like Peptide 1/metabolism , Hippocampus/metabolism , Hippocampus/pathology , Insulin-Secreting Cells/pathology , Insulin-Secreting Cells/ultrastructure , Malondialdehyde/metabolism , Mice , Mice, Inbred C57BL , Streptozocin , Superoxide Dismutase/metabolism
12.
Article in Chinese | MEDLINE | ID: mdl-24386815

ABSTRACT

OBJECTIVE: To investigate the relationship between connective tissue growth factor (CCN5) and hepatic stellate cell (HSC) activation as well as the mechanism of action. METHODS: As the research object, LX-2 cells were stimulated with transforming growth factor-beta1 ( TGF-(beta1), and the protein expression levels of CCN5 and CCN2 were determined by Western blot; Hepatocyte high expression system of CCN5 was constructed and transfected hepatic stellate cells (HSC) to make CCN5 overexpression; The expression levels of alpha-smooth muscle actin (alpha-SMA) and collagen I were determined by RT-PCR and Western blot. To further study its mechanism of action, Smad2 and phosphorylation level of Smad2 were determined by RT-PCR and Western blot. RESULTS: Under normal circumstances, CCN2 expression levels were much higher than CCN5 in LX-2 cells, while CCN2 expression was significantly higher than CCN5 if LX-2 cells were stimulated by TGF-beta1. However, there was no change for CCN5. Compared with the control group and the vector group, CCN5 was successfully overexpressed in the transfection group, and mRNA and protein levels of alpha-SMA and collagen I were significantly decreased (P < 0.01). Meanwhile, phosphorylation level of Smad2 was also significantly decreased (P < 0.01). CONCLUSION: CCN5, which has the function that inhibits HSC activation, has the opposite role compared with CCN2, therefore, a new idea was proposed for the prevention and treatment of liver fibrosis.


Subject(s)
Actins/metabolism , CCN Intercellular Signaling Proteins/metabolism , Collagen Type I/metabolism , Connective Tissue Growth Factor/metabolism , Hepatic Stellate Cells/metabolism , Repressor Proteins/metabolism , Cell Line , Humans , Liver Cirrhosis/metabolism , Liver Cirrhosis/pathology , Smad2 Protein/metabolism
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(7): 1862-7, 2011 Jul.
Article in Chinese | MEDLINE | ID: mdl-21942040

ABSTRACT

Spectra and influences of Rayleigh backscattering (RB) and stimulated Brillouin scattering (SBS) in the fiber-optic distributed disturbance sensor (FDDS) were investigated. Models of RB, double RB (DRB) and SBS in long fibers were established. By numerical simulation, it was found that optical signal-to-noise ratio is extraordinarily reduced due to SBS and RB, which results in location errors. Numerical results were confirmed by experiments and helpful to improving the location precision for applications with long monitored length.

14.
Opt Express ; 19(11): 10959-66, 2011 May 23.
Article in English | MEDLINE | ID: mdl-21643356

ABSTRACT

We investigate a two-dimensional low F-number dual micro-axilens array with binary structures based on a rigorous electromagnetic theory. The focal characteristics of a binary dual micro-axilens array (BDMA), including axial performances (focal depth and focal shift) and transverse performances (focal spot size and diffraction efficiency), have been analyzed in detail for different F-numbers, different incident polarization (TE and TM) waves, and different distances between micro-axilens. Numerical results reveal that the interference effect of a BDMA is not very evident, which is useful for building a BDMA with a high fill factor, and the focal characteristics of a BDMA are sensitive to the polarization of an incident wave. The comparative results have also shown that the diffraction efficiency of a BDMA will increase and the focal spot size of a BDMS will decrease when the F-number increases, for both TE polarization and TM polarization, respectively. It is expected that this investigation will provide useful insight into the design of micro-optical elements with high integration.

15.
Biochem Biophys Res Commun ; 408(4): 674-9, 2011 May 20.
Article in English | MEDLINE | ID: mdl-21539807

ABSTRACT

In Synechocystis sp. PCC 6803, the loop domain (aa 1-70) of the phycobilisome core-membrane linker, L(CM), was found to interact with the glycosyl transferase homolog, Sll1466. Growth of a Sll1466 knock-out mutant was slightly faster in low light, but strongly inhibited in high light; the phenotype is discussed in relation to the regulation of light energy transfer to photosystem II. At the molecular level, the mutant shows the following changes compared to the wild type: (1) a smaller size and higher mobility of phycobilisomes on the thylakoid membrane, and (2) a changed lipid composition of the thylakoid membrane, especially decreased amounts of digalactosyl diacylglycerol. These results indicate a profound regulatory role for Sll1466 in regulating photosynthetic energy transfer.


Subject(s)
Glycosyltransferases/metabolism , Light , Photosynthesis , Radiation Tolerance , Synechocystis/enzymology , Synechocystis/radiation effects , Glycosyltransferases/chemistry , Glycosyltransferases/genetics , Mutation , Synechocystis/genetics
16.
Opt Lett ; 35(12): 2091-3, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20548396

ABSTRACT

We theoretically demonstrate third-order lensless ghost diffraction by using a fully classical incoherent light source in which the light beam is detected by two detectors. The resolution and visibility of the obtained diffraction pattern are discussed. It is shown that the resolution of third-order ghost diffraction is determined by the transverse correlation length in the detection plane, while the visibility is affected by the ratio of the transverse length of the imaged object and the transverse size of the light source. Furthermore, we discuss the similarities and differences of second- and third-order lensless ghost diffraction.

17.
Opt Express ; 16(25): 20968-73, 2008 Dec 08.
Article in English | MEDLINE | ID: mdl-19065236

ABSTRACT

This study explores two-dimensional binary sub-wavelength diffractive lenses (BSDLs) for implementing long focal depth and high transverse resolution based on the rigorous electromagnetic theory and the finite-difference time-domain method. Focusing performances, such as the actual focal depth, the ratio between the focal depth of the designed BSDL and the focal depth of the conventional sub-wavelength lens and the spot size of the central lobe at the actual focal plane, for different f-numbers, have been studied in the case of TE incidence polarization wave. The rigorous numerical results indicate that the designed BSDLs indeed have long focal depth and high transverse resolution by modulating the binary sub-wavelength characteristic sizes. Because BSDLs have the ability for monolithic integration and can require only single step fabrication, the investigations may provide useful information for BSDLs' application in micro-optical systems.


Subject(s)
Computer-Aided Design , Lenses , Models, Theoretical , Refractometry/instrumentation , Computer Simulation , Equipment Design , Equipment Failure Analysis , Light , Scattering, Radiation
18.
Guang Pu Xue Yu Guang Pu Fen Xi ; 28(7): 1689-94, 2008 Jul.
Article in Chinese | MEDLINE | ID: mdl-18844190

ABSTRACT

The parameters of polarization maintaining fibers and polarizer, and the splicing angles between them have important influence on the spectral characteristics of lightwave propagating in them. The transmission model of lightwave was established using Jones matrix. For the first time, the effect of degree of polarization, fiber lengths, splicing angles between fibers and between fiber and component on the output spectrum was discussed. It was indicated that the shape of output spectrum of the unpolarized lightwave will not change when the splicing angles between fibers and between fiber and component were not zero, while there were periodical functions added to the output spectrum of polarized of partially polarized lightwave. The result that when the angles were constants, the longer the fibers were, the smaller the periods of periodical functions, and that when the fiber lengths were constants, in a certain range the bigger the angles, the larger the amplitudes of periodical functions, was achieved. The conclusions were verified by experiments and they could supply theoretical guidance for the systems using polarization maintaining fibers and polarizer.

19.
Opt Express ; 16(7): 5130-5, 2008 Mar 31.
Article in English | MEDLINE | ID: mdl-18542612

ABSTRACT

In this paper a novel optical generation approach for binary-phase-coded, direct-sequence ultra-wideband (UWB) signals is experimentally demonstrated. Our system consists of a laser array, a polarization modulator (PolM), a fiber Bragg grating (FBG), a length of single mode fiber, and a photo detector (PD). The FBG, designed based on the superimposed, chirped grating, is used as the multi-channel frequency discriminator. The input electronic Gaussian pulse is modulated on the optical carrier by the PolM and then converted into UWB monocycle or doublet pulses sequence by the multi-channel frequency discriminator. The PolM is used so that the desired binary phase code pattern could be simply selected by adjusting the polarization state of each laser, rather than tuning the laser wavelengths. The desired UWB shape, monocycle or doublet, could be selected by tuning the FBG. Based on our proposed approach, four-chip, binary-phase-coded, DS-UWB sequences with different pulse shapes and code patterns are experimentally demonstrated. The impact of the fiber dispersion on the generated UWB pulses is also discussed in our paper.


Subject(s)
Fiber Optic Technology/instrumentation , Lasers , Photometry/instrumentation , Refractometry/instrumentation , Signal Processing, Computer-Assisted/instrumentation , Telecommunications/instrumentation , Equipment Design , Equipment Failure Analysis
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